Oroville Dam

[jyl]

Traffic maps suggest the folks who drove north to Chico are happier than the folks who drove south toward Sacramento.

[aap1966]

Originally Posted by SoCal911T

*the asterisk is to make note of the short time this thread will last before the PARFtards ruin it.

So, a "You didn't build that" comment is out of line???

[jyl]

What's weather forecast for the watershed?. I see rain starting Wed but not clear how much within the reservoir catchment area?

[pwd72s]

Originally Posted by jyl

What's weather forecast for the watershed?. I see rain starting Wed but not clear how much within the reservoir catchment area?

The 1964 Western Oregon flooding was a "pineapple express"...warm rains out of Hawaii, combined with warm temps causing a heavy snow melt.

Probably the same factors in play with this happening?

[Tobra]

Dean, it has not been warm enough to get too much rain on the snow. There has been some, but I don't think the next round is supposed to be as cold.

It would not be so bad if they did not mismanage the water so much.

[GH85Carrera]

It is the same problem everywhere. Politicians. When the weather is normal spending money on infrastructure is minimized, and the money is wasted on other things. They would rather wait for a catastrophe and then spend 10 time more to fix a problem after the fact. They can go pose in front of a camera and pledge to do "whatever is necessary" to help these citizens in the problem area.

I remember just a few years back Atlanta was having a severe drought. Lake Lanier was almost sucked dry and the "experts" were on the TV saying it might take 20 years to refill. Then the rains came and the lakes were full.

Here in central Oklahoma amazingly the past politicians understood the need for water. They built several drinking water lakes in the 1920s and 1930s. Oklahoma City has several man made lakes in the city limits. One lake is Lake Canton in far NW Oklahoma way outside the city. The city still owns the water rights. In severe droughts OKC will suck that water into the local lakes. They were in a drought up there for a long time and the lake was crazy low. That was a perfect time to expand the spillway and now there is a second spillway for flood control. That second all concrete spillway is done and the lake is full again. We are in another drought now but we have had cycles of drought and drought busting rains since statehood.

[flatbutt]

Do the officials fear a "true" failure? One in which the dam actually breaks apart?

[ossiblue]

Originally Posted by jyl

Various watchdog groups tried to get emergency spillway lined with concrete, state and federal agencies and water utilities refused. That spillway is a big earthern ditch with just a concrete lip.

https://www.google.com/amp/www.mercurynews.com/2017/02/12/oroville-dam-feds-and-state-officials-ignored-warnings-12-years-ago/amp/?client=safari

Originally Posted by GH85Carrera

It is the same problem everywhere. Politicians. When the weather is normal spending money on infrastructure is minimized, and the money is wasted on other things. They would rather wait for a catastrophe and then spend 10 time more to fix a problem after the fact. They can go pose in front of a camera and pledge to do "whatever is necessary" to help these citizens in the problem area.

These two posts sum it up ^^.

It's not just politicians, it's the public, it's the departments, and it's about money. The dam had been in service for nearly 40 years when the push to improve the emergency spillway was happening. The improvements were brought forth by groups often identified as "Tree Huggers" and "Do Gooders"at a time when there had been no historical reason for the improvement. The state, water contractors, and water districts saw the push as an unnecessary expenditure that would result in increased water rates, eventually, for the public. The water departments had the "facts" of the engineering designs and projections as well as the history of the dam on their side. The groups warning of danger had only speculation and hypothetical scenarios which came with a huge price tag.

Hindsight is 20/20. Not defending anyone here, but we need to look at things in the context of their occurrences. In all fairness, there was not much public support in 2005-6 for spending millions of dollars and raising water rates based on a remote possibility. The emergency spillway had never been used in its history. The controlled spillway had been doing its designed job. The dam had never been in danger. The greatest portion of the public who would foot the bill for the improvement lives no where near the dam. Support for the improvement was lukewarm, at best.

[red-beard]

Originally Posted by jyl

Various watchdog groups tried to get emergency spillway lined with concrete, state and federal agencies and water utilities refused. That spillway is a big earthern ditch with just a concrete lip.

https://www.google.com/amp/www.mercurynews.com/2017/02/12/oroville-dam-feds-and-state-officials-ignored-warnings-12-years-ago/amp/?client=safari

Looks lined with concrete to me.



2007 photo, before concrete



And the damage sure makes it look like there is concrete there. I expect the ground was not properly prepared for the concrete overlay, leading to the damage.

[vash]

you should see our highways.

i'm in for a long several months..lots of OT.

some great perspectives posted above. personally, i try to fix things for the long haul. i loose sleep if it isnt done overboard a bit.

[Scott Douglas]

James - That is not the emergency spillway, that is the normal spillway. The emergency spillway is located to the left of that one shown in your picture and just dumps onto an earthen hillside.

[jyl]

That is the main spillway, James's

The emergency spillway is next to that.

[ossiblue]

Yes, the rim of the emergency spillway is just under the time stamp on this photo.


The path of the water and the catch basin for the emergency spillway is seen in this photo. It is all a natural grade once the water leaves the area above the service road, and it is the area of the catch basin that began to erode and work its way back to the concrete rim of the emergency spillway. The spillway is basically a lowered rim of the dam and there is no way to control flow of water over the lower rim except by lowering the level of the lake via the concrete spillway.

[red-beard]

2016 The whole Dam



2007 The Whole Dam

[vash]

here is a pic from 2013 (supposedly)

think it is the same spot?

[ossiblue]

Originally Posted by red-beard

Scott, that is the ONLY spillway on the dam. The regular flow comes out the bottom of the dam.

Not exactly. The concrete spillway is the only controlled spillway. The emergency spillway is, as mentioned, to the left. It's referred to as the emergency spillway because it comes into play only when the level of the lake is unable to be lowered by the concrete spillway and the discharge at bottom of the dam. It functions because the rim is lower than the top of the dam and water is released with no human intervention. In short, in an emergency, the lake overflows beginning at the emergency spillway instead of the dam itself.

[ossiblue]

Originally Posted by vash

here is a pic from 2013 (supposedly)

think it is the same spot?

Here's a picture of the original breach in the spillway. It looks to be in the area just at the bottom of the one you posted, on the right where the
"thumbs up" icon is located.



Once more water was released, the breach opened up more and we got the erosion you see in this photo.


And here's a photo of the emergency spillway rim being breached by the water. Like water overflowing in a glass.


And here's a picture of the erosion caused by the flow over the emergency spillway. Notice the water coming over the area on the far left, which is a parking lot and not part of the emergency spillway rim.

[red-beard]

Originally Posted by ossiblue

Not exactly. The concrete spillway is the only controlled spillway. The emergency spillway is, as mentioned, to the left. It's referred to as the emergency spillway because it comes into play only when the level of the lake is unable to be lowered by the concrete spillway and the discharge at bottom of the dam. It functions because the rim is lower than the top of the dam and water is released with no human intervention. In short, in an emergency, the lake overflows beginning at the emergency spillway instead of the dam itself.

OK, I see it now. It is very hard to see with the aerial photos that the area in question is anything other than a concrete wall.

It seems most of these dams are not being kept up. The dam/levees in the area around here are also at risk and they were concerned about a breech last year, when the level was the highest it had ever been.

They say our issue is over development. But our red-clay ground is not porous. It was simply a HUGE rain event.

[Cajundaddy]

Looks like they have things stabilized for now. Water is no longer overtopping the emergency spillway. They need to drop the level another 50' over the next few days to do emergency repairs to the spillway and prepare for the next round of pineapple express. 4-5 more inches of warm rain are expected to begin Wednesday and run through the week.

Lake Shasta is also near capacity and dumping water as fast as possible in preparation for more heavy rain. The Sacramento river is at flood stage due to maximum release from Shasta dam. I expect the Sacramento delta will be overrun soon if not already from all this water release. Exciting times for Nor Cal right now with way more water than we can capture and store. We need temps to drop 20 degrees to put this into more manageable snowpack instead of deluge runoff.

[island911]

Originally Posted by Crowbob

Good explanation if this video loads...

https://m.youtube.com/watch?v=jIzldNLv8ww&itct=CAYQpDAYByITCNey16e6idICFZl9TgodSZEFcDIHcmVsY XRlZEi-mOPAudaau_0B

Very informative. Thanks.

What's crazy is that this drought/rain extreme happened (under Gov Brown ) back in the 70's. (when global cooling was to blame )

https://realclimatescience.com/2017/02/california-sanctuary-state-for-morons/